////https://leetcode.cn/problems/design-circular-queue/
//循环队列

public class MyCircularQueue {

    public int Front;
    public int rear;
    public int[] elem;

    public MyCircularQueue(int k){
        elem = new int[k+1];
    }

    //入队列
    public boolean enQueue(int val){
        if (isFull()){
            return false;
        }
        elem[rear] = val;
        rear = (rear+1)%elem.length;
        return true;
    }

    //出队列
    public boolean deQueue(){
        if (isEmpty()){
            return false;
        }
        Front = (Front+1)%elem.length;
        return true;
    }

    //获得头元素
    public int Front(){
        if (isEmpty()){
            return -1;
        }
        return elem[Front];
    }

    public int Rear(){
        if (isEmpty()){
            return -1;
        }
        int index = (rear == 0) ?elem.length-1 : rear-1;
        return elem[index];

    }

    //判满
    public boolean isFull(){
        return (rear+1)%elem.length == Front;
    }

    //判空
    public boolean isEmpty(){
        return rear == Front;
    }

}
